Tash Shardborn has this to say:
“In a very real sense, the Keister is the island. But in an equally, and more accurately, real sense the island is the island. Witness the cosmopolitan jumble of Floom, the aromatic mysticisms of the Garden of Smellemental Glee, the monumental juts and caverns of the Knobby Rumple... Behold dank rites and unspeakable atrocities as you scramble your way through the lichenous strew of Stan’s Rug. Prance the loamy frolic of the Soul Patch. Wallow in the ichorous murk of the Imple Slew. Wonder what all those statues are about. Do some other stuff. Try not to get eaten.”
The Whole Hole - A Gadabout’s Guide to Mutha Oith, Volume 01: Keister Island is the first in a series of guidebooks (that’s what “Volume 01” means) designed to immerse the reader within and among the places, peeps, beasts, and happenings of the various realms of Mutha Oith. Join intrepid gadabout Toucanacondor Flaminguez as he tours Keister Island. You’ll explore dozens of locales, meet hundreds of peeps, examine new religions, gawp in awe at wondrous magics, and run in terror from a bunsload of horrifying monstrosities. Here you’ll investigate the Fundamental nature of all things, dabble in smellcasting at the Garden of Smellemental Glee, chug suds with Floom’s elite, and marvel at the bottomless Keister of Gawd. There’s new Holy Crap, new Edges and Hindrances, New PC species, new setting rules, and twenty pages of new monsters. Seriously, stop reading the back cover and just buy the goosin’ thing already.